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<h2>Mantiuk'08</h2>

<p>This operator
applies the display adaptive tone mapping, which attempts to
preserve contrast of an input (HDR) image as close as
possible given the characteristic of an output display. Use
this tone mapping operator if you want to preserve original
image appearance, or slightly enhance contrast while maintaining 
the natural look of images. The
operator can also compensate for ambient light reflections
on a screen, and for varying dynamic range and brightness of
a display. The operator is suitable for video sequences as
it prevents high-frequency changes in tone-curve between
consecutive frames, which would result in flickering. Note
that the temporal filtering is always active and there is no
need to specify an argument to switch it on.</p>

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<p style="margin-top: 1em">More details can be found
in:</p> </td>
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<p style="margin-left:11%;">Rafal Mantiuk, Scott Daly and
Louis Kerofsky. <br>
Display Adaptive Tone Mapping. <br>
In: ACM Transactions on Graphics 27 (3), 2008. <br>
http://www.mpi-inf.mpg.de/resources/hdr/datmo/</p>

<p style="margin-left:0%; margin-top: 1em">If you find
this TMO useful in your research project, please cite the
paper above.</p>
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<p style="margin-top: 1em">This operator also employs color
correction mechanism from:</p></td></tr>
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<p style="margin-left:11%;">Radoslaw Mantiuk, Rafal
Mantiuk, Anna Tomaszewska, Wolfgang Heidrich. <br>
Color Correction for Tone Mapping. <br>
In: Computer Graphics Forum (Proc. of
EUROGRAPHICS&rsquo;09), 28(2), 2009. <br>
http://zgk.wi.ps.pl/color_correction/</p>

<p>The result of
this TMO does not usually require gamma correction.</p>

<h3>OPTIONS</h3>

<DT><B>Color Saturation</B><DD>
<p>
Decrease or increase color saturation after tone mapping. Default
value <B>1</B> attempts to preserve color appearance of the original
image. Use values &gt;1 to increase and &lt;1 to decrease color saturation.
<DT><B>Contrast Enhancement</B><DD>
<p>
By default this tone-mapper attempts to preserve contrast of an input
image. This parameter controls whether the contrast of an
input image should be enhanced before tone-mapping. For example
<B>1.15</B> boosts contrast by 15%. Note that if a target display
does not offer sufficient dynamic range, contrast may be enhanced only
for selected tone-values (those that dominate in an image) or not
enhanced at all.
<DT><B>Luminance Level</B><DD>
<p>
Tells the
tone-mapper what luminance level in the input image should be mapped
to the maximum luminance of a display. Since HDR images contain only
relative luminance information, tone-mapper does not know how bright
should be the scene. This option is meant to fix this problem by
providing tone-mapper with the information what luminance level in an
input image should be perceived as a diffuse white surface. Default is
<I>none</I>, which means that no such mapping will be enforced and
tone-mapper is free to find an optimal brightness for a given
image. This is a recommended setting for HDR images.

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